Cathy O'Neil, data scientist and author of the new book Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy, discussed how some algorithms can have an invisible, but important and destructive impact on people's lives. Decisions about employment, criminal sentencing, and many other areas are now influenced by algorithms and big data. This is a serious problem, argues O'Neil, as there is little transparency about how these systems are constructed or used. This Shorenstein Center Speaker Series event was recorded October 4, 2016, at Harvard Kennedy School.